Thrombotic or thromboembolic occlusion of a cerebral artery is the most common pathophysiologic mechanism of
acute ischemic stroke. An
antithrombotic agent would therefore appear to be an ideal medication for treatment of this condition.
Heparin is an effective
anticoagulant, but it has poor bioavailability and effects on
thrombin and platelets that predispose it to life-threatening complications such as
hemorrhage and
thrombocytopenia. Low-molecular-weight (LMW) heparins have better bioavailability, a higher anti-Xa:anti-IIa ratio, and less effect on platelets than
heparin; yet their heterogeneity has hampered their proper investigation in clinical trials and it has not yet been proven that they exhibit less tendency toward
hemorrhage and
thrombocytopenia than conventional
heparin. The LMW
heparinoid,
Org 10172, is superior to standard
heparin in terms of its bioavailability, anti-Xa:anti-IIa ratio, and lack of effect on platelets. It is less likely than
heparin and many LMW heparins to induce
thrombocytopenia. Like the various heparins,
Org 10172 exhibits dose-dependent hemorrhagic tendencies, yet preliminary studies have found doses that are safe for use in patients with
acute ischemic stroke. These studies also suggest that
Org 10172 may improve outcome and lessen mortality in this population. A prospective, randomized, double-blind, controlled trial is needed to establish the potential efficacy of
Org 10172 in patients who suffer acute or progressing
ischemic stroke.